Thinkific Thinkific Online Course Creation Platform 1.0 is affected by: Cross Site Scripting (XSS). The impact is: execute arbitrary code (remote). The component is: Affected Source code of the website CMS which is been used by many to host their online courses using the Thinkific Platform. The attack vector is: To exploit the vulnerability any user has to just visit the link - https://hacktify.thinkific.com/account/billing?success=%E2%80%AA%3Cscript%3Ealert(1)%3C/script%3E. ¶¶ Thinkific is a Website based Learning Platform Product which is used by thousands of users worldwide. There is a Cross Site Scripting (XSS) based vulnerability in the code of the CMS where any attacker can execute a XSS attack. Proof of Concept & Steps to Reproduce: Step1 : Go to Google.com Step 2 : Search for this Dork site:thinkific.com -www Step 3 : You will get a list of websites which are running on the thinkific domains. Step 4 : Create account and signin in any of the website Step 5 : Add this endpoint at the end of the domain and you will see that there is a XSS Alert /account/billing?success=%E2%80%AA<script>alert(1)</script> Step 6 : Choose any domains from google for any website this exploit will work on all the websites as it is a code based flaw in the CMS Step 7 : Thousands of websites are vulnerable due to this vulnerable code in the CMS itself which is giving rise to the XSS attack.

The Thinkific Uploader WordPress plugin through 1.0.0 does not sanitise and escape its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks against other administrators.